Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 218
Filtrar
1.
Front Neurol ; 15: 1348862, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38725649

RESUMEN

Background: Post-stroke aphasia (PSA) is one of the most devastating symptoms after stroke, yet limited treatment options are available. Prolonged intermittent theta burst stimulation (piTBS) is a promising therapy for PSA. However, its efficacy remains unclear. Therefore, we aim to investigate the efficacy of piTBS over the left supplementary motor area (SMA) in improving language function for PSA patients and further explore the mechanism of language recovery. Methods: This is a randomized, double-blinded, sham-controlled trial. A total of 30 PSA patients will be randomly allocated to receive either piTBS stimulation or sham stimulation for 15 sessions over a period of 3 weeks. The primary outcome is the Western Aphasia Battery Revised (WAB-R) changes after treatment. The secondary outcomes include The Stroke and Aphasia Quality of Life Scale (SAQOL-39 g), resting-state electroencephalogram (resting-state EEG), Event-related potentials (ERP), brain derived neurotrophic factor (BDNF). These outcome measures are assessed before treatment, after treatment, and at 4-weeks follow up. This study was registered in Chinese Clinical Trial Registry (No. ChiCTR23000203238). Discussion: This study protocol is promising for improving language in PSA patients. Resting-state EEG, ERP, and blood examination can be used to explore the neural mechanisms of PSA treatment with piTBS. Clinical trial registration: https://www.chictr.org.cn/index.html, ChiCTR2300074533.

2.
Acta Biochim Pol ; 71: 12461, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721305

RESUMEN

Objective: To analyze the clinical characteristics of primary Sjögren's syndrome (pSS) combined with interstitial lung disease (ILD), so as to provide a theoretical basis for the early diagnosis, treatment and prevention of PSS-ILD. Methods: From October 2017 to January 2022, patients with pSS who were admitted to the Department of Rheumatology at Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine were included in this retrospective study. Patients were divided into the pSS-ILD (102 cases) and pSS-non-ILD groups (154 cases) based on the presence or absence of ILD on high-resolution computed tomography (HRCT). Demographics information, clinical symptoms, laboratory indicators and HRCT features were compared, and the logistic regression analysis was utilized to identify the risk factors. Results: A total of 256 patients were included. Patients with pSS-ILD were more often female, and their age and disease duration were significantly higher than those in the pSS-non-ILD group (p < 0.05). The HRCT imaging classification included ground glass-like shadow (78.4%) and patchy solid shadow (17.6%), and Non-specific interstitial pneumonitis (NSIP) (72.5%) was the predominant typology. Regarding the laboratory indexes, the positive rates of erythrocyte sedimentation rate, C-reactive protein, white blood cell count, neutrophil/lymphocyte ratio, triglycerides, total cholesterol, and anti-SS-A52 antibodies were significantly higher in the pSS-ILD patients than in the pSS-non-ILD group, while the positive rates of anti-synaptic antibodies were lower than in the pSS-non-ILD group, and the differences between two groups were statistically significant (p < 0.05). Logistic regression showed that age >60 years, longer duration of disease, higher triglycerides, and cholesterol were risk factors for pSS-ILD patients. Conclusion: The clinical features of pSS-ILD patients were xerophthalmia, cough and shortness of breath, and HRCT can help to diagnose the disease at an early stage. Age over 60 years, chronic course of disease, and elevated lipid levels are risk factors for ILD in pSS patients, and the relationship between autoimmune antibody levels and the occurrence of ILD needs to be further confirmed in follow-up studies with large sample sizes. These findings have the potential to provide useful information for early diagnosis, treatment, and prevention of the development of pSS-ILD.


Asunto(s)
Enfermedades Pulmonares Intersticiales , Síndrome de Sjögren , Tomografía Computarizada por Rayos X , Humanos , Síndrome de Sjögren/complicaciones , Enfermedades Pulmonares Intersticiales/etiología , Enfermedades Pulmonares Intersticiales/epidemiología , Enfermedades Pulmonares Intersticiales/diagnóstico , Enfermedades Pulmonares Intersticiales/complicaciones , Femenino , Estudios Retrospectivos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto , Anciano , China/epidemiología
3.
Plant Cell Rep ; 43(5): 124, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38643320

RESUMEN

KEY MESSAGE: Two peanut LEC1-type genes exhibit partial functional redundancy. AhNFYB10 could complement almost all the defective phenotypes of lec1-2 in terms of embryonic morphology, while AhNF-YB1 could partially affect these phenotypes. LEAFY COTYLEDON1 (LEC1) is a member of the nuclear factor Y (NF-Y) family of transcription factors and has been identified as a key regulator of embryonic development. In the present study, two LEC1-type genes from Arachis hypogeae were identified and designated as AhNF-YB1 and AhNF-YB10; these genes belong to subgenome A and subgenome B, respectively. The functions of AhNF-YB1 and AhNF-YB10 were investigated by complementation analysis of their defective phenotypes of the Arabidopsis lec1-2 mutant and by ectopic expression in wild-type Arabidopsis. The results indicated that both AhNF-YB1 and AhNF-YB10 participate in regulating embryogenesis, embryo development, and reserve deposition in cotyledons and that they have partial functional redundancy. In contrast, AhNF-YB10 complemented almost all the defective phenotypes of lec1-2 in terms of embryonic morphology and hypocotyl length, while AhNF-YB1 had only a partial effect. In addition, 30-40% of the seeds of the AhNF-YB1 transformants exhibited a decreasing germination ratio and longevity. Therefore, appropriate spatiotemporal expression of these genes is necessary for embryo morphogenesis at the early development stage and is responsible for seed maturation at the mid-late development stage. On the other hand, overexpression of AhNF-YB1 or AhNF-YB10 at the middle to late stages of Arabidopsis seed development improved the weight, oil content, and fatty acid composition of the transgenic seeds. Moreover, the expression levels of several genes associated with fatty acid synthesis and embryogenesis were significantly greater in developing AhNF-YB10-overexpressing seeds than in control seeds. This study provides a theoretical basis for breeding oilseed crops with high yields and high oil content.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arachis/genética , Arachis/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Fitomejoramiento , Ácidos Grasos/metabolismo , Desarrollo Embrionario , Lípidos , Semillas/metabolismo
4.
Front Surg ; 11: 1293049, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38425376

RESUMEN

Backgrounds: This study aims to evaluate the clinical outcome of intramedullary nail supplemented by buttress plate or cable in the treatment of intertrochanteric fracture with broken lateral wall. Methods: From May 2015 to January 2022, patients with unstable intertrochanteric femoral fractures underwent intramedullary fixations strengthened with buttress plates or cables, which depended on the lateral femur wall fragment type. The clinical and radiographic results were compared between the two groups. The hip function was evaluated according to the Harris Hip Scoring (HHS) system. Results: Forty-one patients who sustained intertrochanteric fracture + broken lateral wall were enrolled. Of these, thirty-four received a minimum of twelve months of follow-ups. No statistically significant differences in baseline and operative data were proved between these groups (p > 0.05). Three patients were observed fat liquefaction after surgery (plate group: 2 cases, cable group: 1 case). All patients could sustain partial/full weight-bearing and no case underwent subsequent operation. The HHS of the last follow-up presented 83.6 ± 4.9 points in the plate group and 83.8 ± 3.7 points in the cable group. Conclusions: Intertrochanteric femoral fracture with broken lateral wall is an unstable injury type, the operative treatments of which have been challenging and controversial over the years. Augmentation of intramedullary nailing system using plate/cable contributes to reconstructing the lateral femur wall.

5.
J Biochem Mol Toxicol ; 38(1): e23517, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37702107

RESUMEN

Bacterial endotoxin lipopolysaccharide (LPS)-induced inflammatory response and ferroptosis play an important role in urinary tract infections. Tolterodine has been used as a urinary tract antispasmodic and anticholinergic agent. However, the effects of Tolterodine against LPS-induced insults in human bladder epithelial cells (hBECs) have not been reported before. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase release assays to determine the cell viability, reactive oxygen species (ROS) and malondialdehyde level detection were used to determine the level of oxidative stress, enzyme-linked immunosorbent assay and Western blot analysis were used to detect the protein level. In the current study, we found that Tolterodine ameliorated LPS-induced production of ROS and lipid oxidation in hBECs. Interestingly, Tolterodine inhibited the production of interleukin 6, interleukin-1ß, and tumor necrosis factor α. Also, Tolterodine reduced the levels of Fe2+ and suppressed ferroptosis by reducing the levels of glutathione peroxidase 4, prostaglandin-endoperoxide synthase 2, and acyl-CoA synthetase long-chain family member 4 in LPS-challenged bladder epithelial cells. Mechanistically, it was shown that Tolterodine restored the nuclear factor E2-related factor 2 (Nrf2)/nuclear factor-κB signaling. Importantly, inhibition of Nrf2 with its specific inhibitor ML385 abolished the protective effects of Tolterodine in the inflammatory response and ferroptosis, suggesting that the effects of Tolterodine are mediated by Nrf2. Based on these findings, we conclude that Tolterodine might serve as a promising agent for the treatment of LPS-induced bladder inflammation.


Asunto(s)
Ferroptosis , Lipopolisacáridos , Humanos , Especies Reactivas de Oxígeno/metabolismo , Lipopolisacáridos/toxicidad , Tartrato de Tolterodina , Factor 2 Relacionado con NF-E2/metabolismo , Vejiga Urinaria/metabolismo , Células Epiteliales/metabolismo
6.
Rev Sci Instrum ; 94(4)2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38081290

RESUMEN

Vortex dynamics has attracted tremendous attention for both fundamental physics and applications of type-II superconductors. However, methods to detect local vortex motion or vortex jump with high sensitivity are still scarce. Here, we fabricated soft point contacts on the clean layered superconductor 2H-NbSe2, which are demonstrated to contain multiple parallel micro-constrictions by scanning electronic microscopy. Andreev reflection spectroscopy was then studied in detail for the contacts. Differential conductance taken at fixed bias voltages was discovered to vary spontaneously over time in various magnetic fields perpendicular to the sample surface. The conductance variations become invisible when the field is zero or large enough, or parallel to the sample surface, which can be identified as the immediate consequence of vortex motion across a finite number of micro-constrictions. These results demonstrate point contact Andreev reflection spectroscopy to be a new potential way with a high time resolution to study the vortex dynamics in type-II superconductors.

7.
Small ; : e2311452, 2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38145341

RESUMEN

The highly selective electrochemical conversion of methanol to formate is of great significance for various clean energy devices, but understanding the structure-to-property relationship remains unclear. Here, the asymmetric charge polarized NiCo prussian blue analogue (NiCo PBA-100) is reported to exhibit remarkable catalytic performance with high current density (210 mA cm-2 @1.65 V vs RHE) and Faraday efficiency (over 90%). Meanwhile, the hybrid water splitting and Zinc-methanol-battery assembled by NiCo PBA-100 display the promoted performance with decent stability. X-ray absorption spectroscopy (XAS) and operando Raman spectroscopy indicate that the asymmetric charge polarization in NiCo PBA leads to more unoccupied states of Ni and occupied states of Co, thereby facilitating the rapid transformation of the high-active catalytic centers. Density functional theory calculations combining operando Fourier transform infrared spectroscopy demonstrate that the final reconstructed catalyst derived by NiCo PBA-100 exhibits rearranged d band properties along with a lowered energy barrier of the rate-determining step and favors the desired formate production.

8.
ACS Appl Mater Interfaces ; 15(47): 54952-54965, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37966900

RESUMEN

Flexible sensors produced through three-dimensional (3D) printing have exhibited promising results in the context of underwater sensing detection (for applications in navigational vehicles and human activities). However, underwater vehicles and activities such as swimming and diving are highly susceptible to drag, which can cause negative impacts such as reduced speed and increased energy consumption. Additionally, microbial adhesion can shorten the service life of these vehicles. However, natural organisms are able to circumvent such problems, with shark skin offering excellent barrier properties and ruffled papillae providing effective protection against fouling. Here, we show that a sandwich system consisting of a spraying layer, conductive elastomer composite, and encapsulation layer can be printed for multifunctional integrated underwater sensors. The modulated viscoelastic properties of liquid metal form the foundation for printing features, while its pressure-activated properties offer the potential for switchable sensors. An integrated drag reduction and antifouling layer were created by combining the shark skin surface shield scale structure with the lotus leaf surface papillae structure. A 3D-printed flexible sensor was designed using our approach to monitor attitude changes and strain in underwater environments, showcasing its capabilities. Our printed sensors can reduce biological attachment density by more than 50% and reduce underwater drag by 8.6-10.3%.

9.
Bioorg Chem ; 141: 106906, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37837728

RESUMEN

Parkinson's disease (PD) is the second most common neurodegenerative disease. Several single gene mutations involved in PD have been identified such as leucine-rich repeat kinase 2 (LRRK2), the most common cause of sporadic and familial PD. Its mutations have attracted much attention to therapeutically targeting this kinase. To date, many compounds including small chemical molecules with diverse scaffolds and RNA agents have been developed with significant amelioration in preclinical PD models. Currently, five candidates, DNL201, DNL151, WXWH0226, NEU-723 and BIIB094, have advanced to clinical trials for PD treatment. In this review, we describe the structure, pathogenic mutations and the mechanism of LRRK2, and summarize the development of LRRK2 inhibitors in preclinical and clinical studies, trying to provide an insight into targeting LRRK2 for PD intervention in future.


Asunto(s)
Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/tratamiento farmacológico , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Leucina , Proteínas Serina-Treonina Quinasas/genética , Mutación
10.
Micromachines (Basel) ; 14(10)2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37893346

RESUMEN

Electrochemical supercapacitors have attracted significant attention due to their large capacity, high-power output, and long cycle life. However, despite extensive studies and advancements in developing highly porous electrode materials, little quantitative research on the impact of pore geometry on electrochemical responses has been conducted. This paper presents the first quantitative investigation of the relationship between electrochemical capacitive responses and pore geometries at the nanoscale. To achieve this, we constructed a uniform cylindrical pore array with controllable pore diameter and depth by using anodized aluminum oxide (AAO) to serve as a template and atomic layer deposition (ALD) technology for TiN conductive layer decoration. Our findings reveal that, at the nanoscale, increasing the specific surface area through pore diameter and depth does not proportionally increase the capacitive response, even at low scan rates. Meanwhile, we observe a critical pore parameter (170/5000 nm, diameter/depth), where the specific capacitance density and characteristic frequency dramatically decrease with a further increase in the pore aspect ratio. These results indicate that blindly pursuing the absolute specific surface area of the electrode material is not advisable. Instead, optimal pore geometry should be designed based on the desired operational conditions, and this work may serve as valuable guidance.

11.
Nanoscale ; 15(42): 17006-17013, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37831435

RESUMEN

Layered narrow bandgap quasi-two-dimensional (2D) transition metal dichalcogenides (TMDs) demonstrated excellent performance in long-wave infrared (LWIR) detection. However, the low light on/off ratio and specific detectivity (D*) due to the high dark current of the device fabricated using a single narrow bandgap material hindered its wide application. Herein, we report a type-III broken-gap band-alignment WSe2/PdSe2 van der Waals (vdW) heterostructure. The heterodiode device has a prominently low dark current and exhibits a high photoresponsivity (R) of 55.3 A W-1 and a high light on/off ratio >105 in the visible range. Notably, the WSe2/PdSe2 heterodiode shows an excellent uncooled LWIR response, with an R of ∼0.3 A W-1, a low noise equivalence power (NEP) of 4.5 × 10-11 W Hz-1/2, and a high D* of 1.8 × 108 cm Hz1/2 W-1. This work provides a new approach for designing high-performance room-temperature operational LWIR photodetectors.

12.
Pak J Med Sci ; 39(4): 1040-1044, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37492340

RESUMEN

Objective: To analyze the effects of sodium hyaluronate administration on the serum levels of antioxidase, substance P (SP), and neuropeptide Y (NPY) in patients undergoing locking plate fixation (LPF) for tibial plateau fractures (TPF). Methods: We retrospectively analyzed the records of 66 patients with TPF who received treatment in the Beijing Chao-yang Hospital[PJMS1][2] from February 2017 to August 2020. According to the treatment records, 33 patients underwent LPF surgery (control-group), and 33 patients underwent LPF plus sodium hyaluronate treatment (observation-group). The levels of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT) and total antioxidant capacity (TAC)), SP and NPY. Results: Seven days after LPF operations, both groups showed lower levels of SOD, CAT, and TAC compared to pre-surgery levels, while levels of SP and NPY were higher. However, the observation group showed higher levels of SOD, CAT, and TAC compared to the control group, and lower levels of SP and NPY in the control group (P<0.05). Conclusion: The treatment of TPF with LPF plus sodium hyaluronate administration has been shown to effectively reduce oxidative stress reactions, improve SP and NPY levels.[PJMS3][4].

14.
BMJ Open ; 13(6): e060274, 2023 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328181

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of botulinum toxin (BTX) for motor dysfunction in Parkinson's disease (PD). DESIGN: Systematic review and meta-analysis. DATA SOURCES: Searches of PubMed, EMBASE and the Cochrane Library, from database inception to 20 October 2022. ELIGIBILITY CRITERIA: Studies reported in English with adult PD patients treated with BTX. DATA EXTRACTION AND SYNTHESIS: Primary outcomes were United Parkinson's Disease Rate Scale Section (UPDRS) III (or its items) and Visual Analogue Scale (VAS). Secondary outcomes were UPDRS-II (or its items), Freezing of Gait Questionnaire (FOG-Q), Timed Up and Go test (TUG) and treatment-related adverse events (TRAEs). Mean difference (MD) or standardised MD (SMD) before and after treatment with 95% CIs were used for continuous variables and risk ratios (RRs) with 95% CIs was used for TRAEs. RESULTS: Six randomised controlled trials (RCTs) and six non-RCTs (case series) were included (ntotal=224 participants, nRCT=165). No significant difference was found in pooled results of UPDRS-III (available in four RCTs and two non-RCTs, SMD=-0.19, 95% CI -0.98 to 0.60), UPDRS-II (four RCTs and one non-RCT, SMD=-0.55, 95% CI -1.22 to 0.13), FOG-Q (one RCT and one non-RCT, SMD=0.53, 95% CI -1.93 to 2.98) or the risk of TRAEs (five RCTs, RR 0.87, 95% CI 0.37 to 2.01). Significant decreases were found in pooled VAS score (three RCTs and five non-RCTs, MD=-2.14, 95% CI -3.05 to -1.23) and TUG (MD=-2.06, 95% CI -2.91 to -1.20) after BTX treatment. CONCLUSIONS: BTX may not be associated with motor symptoms alleviation, although it benefits pain alleviation and functional mobility improvement.


Asunto(s)
Toxinas Botulínicas , Enfermedad de Parkinson , Adulto , Humanos , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/tratamiento farmacológico , Toxinas Botulínicas/uso terapéutico
15.
Inorg Chem ; 62(26): 10490-10496, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37340884

RESUMEN

Realizing a highly efficient oxygen evolution reaction (OER) process is of great significance for hydrogen energy development. The main challenge still lies in fabricating superior electrocatalysts with favorable performance. Constructing electrocatalysts with ingenious lattice modifications is a considerable way for the rational design of highly active catalytic centers. Here, theoretical calculations predict that the lattice incorporation of Se atoms can effectively enhance the reaction activity of OER with a decreased energy barrier for the rate-determining step. To obtain the corresponding desired electrocatalyst, the optimized lattice Se-modified CoOOH, with the ideal OER performance of low overpotential and stability, was delicately designed and fabricated by the electrochemical activation of the Co0.85Se precatalyst. X-ray absorption spectroscopy (XAS) demonstrates that lattice incorporation is more likely to be generated in Co0.85Se compared to CoSe2 and CoO precatalysts, which promoted the subsequent OER process. This work clarified the correlation between the precatalyst and the lattice-modified final catalyst in connection with electrochemical reconstruction.

16.
Front Aging Neurosci ; 15: 1153973, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37228252

RESUMEN

Background: There is still a large demand for effective treatments to delay disease deterioration in amyotrophic lateral sclerosis (ALS). Typical symptoms of ALS are considered "flaccidity syndrome" in traditional Chinese medicine (TCM). Huoling Shengji Granule (HLSJ) is a TCM formula used to treat flaccidity syndrome. Results of preclinical tests and a previous clinical study support HLSJ as a novel drug for ALS patients. This trial proposed to examine whether a 48-week course of HLSJ is effective and safe for ALS patients diagnosed with the Chinese medicine syndrome of spleen qi insufficiency and kidney yang deficiency. Methods and analysis: In this phase II, multicenter, randomized, double-blind, riluzole parallel-controlled, superiority-design study, eligible participants had the equal opportunity to be assigned to receive either HLSJ or riluzole randomly. Eleven specialized ALS centers in Mainland China will recruit 144 patients for this trial. The primary and secondary outcomes included the change in the ALSFRS-R score and the Rasch-Built Overall Amyotrophic Lateral Sclerosis Disability Scale (ROADS) from baseline to Week 48. Discussion: Here, we endeavored to evaluate TCM for ALS using a standard evidence-based approach for the first time. In addition, the ROADS, a self-report linear-weighted questionnaire, was selected as a secondary outcome measure. We expect to offer a new reference for the outcome evaluation of ALS trials.Clinical trial registration:http://www.Chictr.org.cn, identifier ChiCTR2100044085.

17.
Adv Mater ; 35(30): e2302467, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37074628

RESUMEN

Metal phthalocyanine (MPc) material with a well-defined MN4 moiety offers a platform for catalyzing the oxygen reduction reaction (ORR), while the practical performance is often limited by the insufficient O2 adsorption due to the planar MN4 configuration. Here, a design (called Gr-MG -O-MP Pc) is proposed, where the metal of MPc (MP ) is axially coordinated to a single metal atom in graphene (Gr-MG ) through a bridge-bonded oxygen atom (O), introducing effective out-of-plane polarization to promote O2 adsorption on MPc. Manipulating the out-of-plane polarization charge by varying types of MP and MG (MP  = Fe/Co/Ni, MG  = Ti/V/Cr/Mn/Fe/Co/Ni) in the axial coordination zone of -MG -O-MP - are examined by density functional theory simulations. Among them, the catalyst of Gr-V-O-FePc stands out with the highest calculated O2 adsorption energy, which is synthesized successfully and verified by systemic X-ray absorption spectroscopy measurements. Importantly, it delivers a remarkable ORR performance with half-wave potential of 0.925 V (versus reversible hydrogen electrode) and kinetic current density of 26.7 mA cm-2 . This thus demonstrates a new and simple way to pursue high catalytic performance by inducing out-of-plane polarization in catalysts.

18.
Int J Nanomedicine ; 18: 1063-1083, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36879890

RESUMEN

Purpose: To investigate the effect of macrophage exosomal long non-coding (lnc)RNAs on bone mesenchymal stem cell (BMSC) osteogenesis and the associated mechanism. Methods: Rat BMSCs and spleen macrophages were co-cultured with serum derived from the fracture microenvironment of rat tibia. BMSC osteogenesis was evaluated using Alizarin red staining and the expression of BMP-2, RUNX2, OPN, and OC mRNA. BMSC osteogenesis was evaluated after co-culture with macrophages stimulated using hypoxic conditions or colony-stimulating factor (CSF). The uptake of macrophage-derived exosomes by BMSCs was evaluated using the exosome uptake assay. High-throughput sequencing and bioinformatics analyses were performed to identify key lncRNAs in the macrophage exosomes. The effect of lncRNA expression levels on BMSC osteogenesis was also assessed using a lncRNA overexpression plasmid and siRNA technology. M1 and M2 macrophages were distinguished using flow cytometry and the key exosomal lncRNA was detected by in situ hybridization. Results: In the fracture microenvironment, macrophages (stimulated using either hypoxia or CSF) significantly increased the osteogenic ability of BMSCs. We showed that BMSCs assimilated macrophage-derived vesicles and that the inhibition of exosomal secretion significantly attenuated the macrophage-mediated induction of BMSC osteogenesis. The hypoxia condition led to the up-regulation of 310 lncRNAs and the down-regulation of 575 lncRNAs in macrophage exosomes, while CSF stimulation caused the up-regulation of 557 lncRNAs and the down-regulation of 407 lncRNAs. In total, 108 lncRNAs were co-up-regulated and 326 lncRNAs were co-down-regulated under both conditions. We eventually identified LOC103691165 as a key lncRNA that promoted BMSC osteogenesis and was expressed at similar levels in both M1 and M2 macrophages. Conclusion: In the fracture microenvironment, M1 and M2 macrophages promoted BMSC osteogenesis by secreting exosomes containing LOC103691165.


Asunto(s)
Exosomas , ARN Largo no Codificante , Animales , Ratas , ARN Largo no Codificante/genética , Osteogénesis , Regulación hacia Abajo , Regulación hacia Arriba
19.
Nanomaterials (Basel) ; 13(5)2023 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-36903821

RESUMEN

BiFeO3-based ceramics possess an advantage over large spontaneous polarization and high Curie temperature, and are thus widely explored in the field of high-temperature lead-free piezoelectrics and actuators. However, poor piezoelectricity/resistivity and thermal stability of electrostrain make them less competitive. To address this problem, (1 - x) (0.65BiFeO3-0.35BaTiO3)-xLa0.5Na0.5TiO3 (BF-BT-xLNT) systems are designed in this work. It is found that piezoelectricity is significantly improved with LNT addition, which is contributed by the phase boundary effect of rhombohedral and pseudocubic phase coexistence. The small-signal and large-signal piezoelectric coefficient (d33 and d33*) peaks at x = 0.02 with 97 pC/N and 303 pm/V, respectively. The relaxor property and resistivity are enhanced as well. This is verified by Rietveld refinement, dielectric/impedance spectroscopy and piezoelectric force microscopy (PFM) technique. Interestingly, a good thermal stability of electrostrain is obtained at x = 0.04 composition with fluctuation η = 31% (Smax'-SRTSRT×100%), in a wide temperature range of 25-180 °C, which is considered as a compromise of negative temperature dependent electrostrain for relaxors and the positive one for ferroelectric matrix. This work provides an implication for designing high-temperature piezoelectrics and stable electrostrain materials.

20.
Pediatr Radiol ; 53(8): 1685-1697, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36884052

RESUMEN

BACKGROUND: Accurate segmentation of neonatal brain tissues and structures is crucial for studying normal development and diagnosing early neurodevelopmental disorders. However, there is a lack of an end-to-end pipeline for automated segmentation and imaging analysis of the normal and abnormal neonatal brain. OBJECTIVE: To develop and validate a deep learning-based pipeline for neonatal brain segmentation and analysis of structural magnetic resonance images (MRI). MATERIALS AND METHODS: Two cohorts were enrolled in the study, including cohort 1 (582 neonates from the developing Human Connectome Project) and cohort 2 (37 neonates imaged using a 3.0-tesla MRI scanner in our hospital).We developed a deep leaning-based architecture capable of brain segmentation into 9 tissues and 87 structures. Then, extensive validations were performed for accuracy, effectiveness, robustness and generality of the pipeline. Furthermore, regional volume and cortical surface estimation were measured through in-house bash script implemented in FSL (Oxford Centre for Functional MRI of the Brain Software Library) to ensure reliability of the pipeline. Dice similarity score (DSC), the 95th percentile Hausdorff distance (H95) and intraclass correlation coefficient (ICC) were calculated to assess the quality of our pipeline. Finally, we finetuned and validated our pipeline on 2-dimensional thick-slice MRI in cohorts 1 and 2. RESULTS: The deep learning-based model showed excellent performance for neonatal brain tissue and structural segmentation, with the best DSC and the 95th percentile Hausdorff distance (H95) of 0.96 and 0.99 mm, respectively. In terms of regional volume and cortical surface analysis, our model showed good agreement with ground truth. The ICC values for the regional volume were all above 0.80. Considering the thick-slice image pipeline, the same trend was observed for brain segmentation and analysis. The best DSC and H95 were 0.92 and 3.00 mm, respectively. The regional volumes and surface curvature had ICC values just below 0.80. CONCLUSIONS: We propose an automatic, accurate, stable and reliable pipeline for neonatal brain segmentation and analysis from thin and thick structural MRI. The external validation showed very good reproducibility of the pipeline.


Asunto(s)
Aprendizaje Profundo , Recién Nacido , Humanos , Reproducibilidad de los Resultados , Neuroimagen , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador/métodos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...